Cannot read backed up photos

I periodically back up my photos to CD and normally when I insert the disc it opens i Photo and displays the thumbnails. On at least two recent backups ipoto does not open and I get the following message

" You canít open your current photo library using this version of iPhoto. You have made changes to your photo library using a newer version of iPhoto. Please quit and use the latest version of iPhoto."

I suspect you have identified the problem. Back when I burned those discs I think I had 9.2.3 on the Mac but it gave me all kinds of problems so I reverted to 7.1.5. Tonight I reinstalled 9.2.3 form the Time Machine but it won't open, says I should check with the developer to be sure it is compatible with my version of OS X but from what I read 9.2.3 is compatible with 10.6.8 which is where I am. Leaves me mystified

Have not done any testing going back and forth between versions, so taking a guess here.

Would try re-downloading it from your "purchased" items in the App Store. (edit: perhaps try the update below first)

Am pretty sure iPhoto is one of those apps that installs part of it's data into system folders. Since I don't know how you uninstalled it or if you just did a restore of your system to a previous state (which would delete all those system files it installed), not sure that restoring only the app from TM would reinstall all of it's required parts.

It's possible downloading the 9.2.3 update might repair it - here.
I believe that is the last update compatible with Snow Leopard also.

I cannot be held responsible for the things that come out of my mouth.
In the Windows world, most everything folks don't understand is called a virus.